新增觸控支援

如要處理觸控輸入事件，請讀取遊戲迴圈中的陣列 motionEvents。這些事件包含自上次清除這些陣列之後發生的事件。包含的事件數量會儲存在 motionEventsCount 中。

  1. 疊代並處理遊戲迴圈中的各個事件。在這個範例中，以下程式碼會疊代 motionEvents，並透過 handle_event 進行處理：

    for(size_t i = 0; i < mApp->motionEventsCount; ++i) {
  GameActivityMotionEvent* motionEvent = mApp->motionEvents[i];

  int action = motionEvent->action;
  int actionMasked = action & AMOTION_EVENT_ACTION_MASK;
  int ptrIndex = (action & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK) >>
    AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;

  struct CookedEvent ev;
  memset(&ev, 0, sizeof(ev));

  if (actionMasked == AMOTION_EVENT_ACTION_DOWN ||
    actionMasked == AMOTION_EVENT_ACTION_POINTER_DOWN) {
      ev.type = COOKED_EVENT_TYPE_POINTER_DOWN;
  } else if (actionMasked == AMOTION_EVENT_ACTION_UP ||
    actionMasked == AMOTION_EVENT_ACTION_POINTER_UP) {
      ev.type = COOKED_EVENT_TYPE_POINTER_UP;
  } else {
      ev.type = COOKED_EVENT_TYPE_POINTER_MOVE;
  }

  ev.motionPointerId = motionEvent->pointers[ptrIndex].id;
  ev.motionIsOnScreen = motionEvent->source == AINPUT_SOURCE_TOUCHSCREEN;
  ev.motionX = GameActivityPointerInfo_getX(
    &motionEvent->pointers[ptrIndex]);
  ev.motionY = GameActivityPointerInfo_getY(
    &motionEvent->pointers[ptrIndex]);

  if (ev.motionIsOnScreen) {
    // Use screen size as the motion range.
    ev.motionMinX = 0.0f;
    ev.motionMaxX = SceneManager::GetInstance()->GetScreenWidth();
    ev.motionMinY = 0.0f;
    ev.motionMaxY = SceneManager::GetInstance()->GetScreenHeight();
  }

  handle_event(&ev);
}

  2. 完成後，請記得清除剛處理的事件佇列：

    android_app_clear_motion_events(mApp);